H1B, H4 & H4 EAD Extension

[shevas2003]

I have my H1B and wife's H4 stamp & H4 EAD valid until April 2022. It has been a while since we have been in touch with wait times for extension and I am a Canadian citizen so I do not need a stamped visa, just an approval from USCIS. My wife is working and I want to make sure we apply for our extension in a timely manner if the wait times are too long. What are the wait times and can we still file all 3 extensions together under Premium processing for the H1B like we did in the previous years? If not, what is the best way to approach applying for extension and the timeline so my wife's job is not interrupted.
Thanks in advance

[shevas2003]

BUMP, please share if anybody has been in this situation. I am trying to gauge the timeline to get started on the extension process